Celtic manager Neil Lennon has rounded on elements of the club's support following the display of a controversial banner.
He's accused some Hoops fans of engaging in "dangerous rhetoric".
A banner with the words 'Shoot the board' was hung on fences erected to keep fans away from the Parkhead entrance on Tuesday.
There's been simmering anger among Celtic supporters at majority shareholder Dermot Desmond and chief executive Peter Lawwell in recent weeks.
Protests outside the stadium have been broken up by Glasgow police, while the Green Brigade fans group have repeatedly called for Desmond and Lawwell to step aside. They're also seeking a change in management.
Celtic have won just one of their last five Scottish Premiership games, and are 13 points adrift of leaders Rangers with two games in hand.
Lawwell and the board have publicly - and repeatedly - backed Lennon to turn things around at the club.
Protesting Celtic fans say Shoot The Board. pic.twitter.com/FwxaMcjxhP
— Graeme Hanna (@graeme818) December 8, 2020
And the manager has appealed for calm among the angrier sects of the Celtic support.
"From some sections of the support it is dangerous rhetoric," Lennon told a press conference, ahead of their final Europa League group game with Lille.
"What I will say is we all want the same thing. Those fans want success, the majority of our fans want success. The players and everybody here want the same thing.
"But we don't like that kind of [shoot the board] language or expression anywhere near the football stadium. It serves no purpose really."
Lawwell and co say Lennon's position will be reviewed in the new year, but the Armagh man has asked everyone to get behind the team as they chase a tenth title in a row.
"I can't speak on behalf of the supporters but it's a cultural thing at the moment. It's a societal, modern-day thing," Lennon said.
"It's not what we want. It doesn't serve any purpose. It certainly doesn't inspire anyone at the club to achieve great things.
"We all want unity. We have got that certainly from the football side of things and we just want the supporters to get behind the team, especially when they need it.
"That's what the Celtic fans do. They've done that for as long as I've been here. When things have got tough they've got right behind the team and that's what we're looking for."